World ocean annual mean absolute geostrophic velocity on marine geoid of EIGEN-6C4 from WOA13 (NCEI Accession 0208329)

This dataset contains annual mean geostrophic velocity calculated at depth corresponding to negative values of the marine geoid. It is calculated from two open sources from the geodetic (EIGEN-6C4) and oceanographic (NCEI) communities. The first source EIGEN-6C4 is a static global combined gravity field model developed by GFZ Potsdam and GRGS Toulouse up to degree and order 2190. The second source is the “World ocean geostrophic velocity inverted from World Ocean Atlas 2013 with the P-vector method” (NCEI accession 0121576). With the given non-positive values of the geoid, N, (i.e., for the oceans), the absolute geostrophic currents (u, v) are easily identified on N with 1 degree resolution from the second dataset except the equatorial zone (5oS – 5oN) due to the non-existence of the geostrophic balance. Altogether, the dataset contains 15,481 (u, v) data pairs. While there is no geostrophic motion at the surface if it coincided with the geoid, the opposite is not valid. This dataset shows that ocean geostrophic velocity doesn't zero at z=N. Data are in netcdf format.